Reversible photoinduced switching of magnetic properties at room temperature of iron oxide particles in self-assembled films containing azobenzene

The use of organized organic assemblies to direct the formation of mesoscop ic inorganic structures presents many possibilities in the development of n ew functional materials. We have designed nano-films containing iron oxide particles, which exhibit magnetic properties at room temperature, and azobe nzene by use of an alternate adsorption technique. Photoisomerization of th e film was accompanied by a geometrically confined structural change, as re flected by changes in the electrostatic field. As a result, we were able to control the magnetic properties of this film by photoillumination at room temperature. (C) 2000 Elsevier Science S.A. All rights reserved.